1. Technical Field
The present invention relates to a power control apparatus and method in a display unit and, more particularly, to a power control apparatus and method wherein, instead of an existing analog switch, a digital switch is utilized for controlling and adjusting a power supply according to input of a sync signal, a display data channel (DDC) signal, or a universal serial bus (USB) signal.
2. Related Art
In some configurations of a display monitor, a special power switch is located closed to a knob installed at a predetermined location on a front surface of a monitor case, and switching on and off of the power to the monitor is accomplished by operation of the knob. Conversely, when the power switch is located a distance from the knob, the power switch cannot be directly turned on and off by operation of the knob, and therefore a special guide between the knob and power switch is necessary for proper operation of the switch. In the latter configuration, an accurate operational distance between the power switch and the knob is mandatory in order to insure proper operation of the power switch.
However, the above-described structure has drawbacks and shortcomings. Notably, a poor switching operation results from a change in the length of the knob, and from an error occurring during assembly of the knob and the power switch inserted into a printed circuit board. Moreover, when the knob is located a distance from the power switch, poor operation can result as a result of a change in the length of the guide which transmits the switching signal between the knob and the power switch. In short, such an arrangement results in the production of inferior goods, as well as in an increase and the production cost. Accordingly, special manufacturing procedures and extra labor is required.
Another disadvantage of contemporary monitors results from the fact that certain data (e.g., DDC data, USB communication data, sync signals) transmitted from the computer to the monitor are not effective when the monitor is turned off.
Certain monitors employ a power switching system which uses an analog switch. However, this has the disadvantage that a separate power switch for the monitor has to be turned on and off whenever a power switch of the computer is turned and off. For such an analog switch, an elastic member is compressed by a pushing motion of the user, and the elastic member returns to an original state when the external force exerted by the user on the power knob is removed. In addition, power switches for the computer and monitor are separately installed, and this increases the production cost. Finally, in such a system, the functions of the signals "DDC, USB and sync" from the computer cannot be carried out or achieved without turning on the monitor.
Therefore, there is a need for the development of a system wherein the functions of the USB signal, DDC signal and sync signal provided by the computer to the monitor are effective even when the monitor is turned off. There is also a need for the development of a such a system in which production cost are cut by use of a digital switch instead of a separate analog power switch for the monitor.